Road-testing machine



July 1, 1930. G. N. LAMB ROAD TESTING MACHINE Filed Dec. 22, 1928 INVENTOR. GEO/P65 N. LAMB A TTORNE Y.

Patented July 1, 1930 ETEiDfiT rarerori lcs eE-onenn. LAMB, or srcnannns, rL mors Roanrss'rrite- MACHINE Application filed December 22, 1928. Serial No. 327,895.

My invention relates to an improvedconstruction of machinefor testing roadways to determine whether they are level. and true. In constructing roadways where the surface is of considerable extent at the same inclination, whether on a level run of roadway or on a grade, it is customary in the specification of the roadway to permit a small amount of variation from exact longitudinal alignment, for example, one quarter of an inch 'in ten feet, and the inspection of such roadways requires considerable care to deter-mine whether the specification has been observed in the particular referred to. By my present 15 invention, I provide a machine consisting of two frame members pivotally connected at their adjacent ends so that the machine may be folded into compact compass when not in use, and wheels preferably mounted at the 539 pivot connect-ionof the frame members and at their other ends, to support the machine on the roadway being tested. It is desirable that the length of the entire machine shall be substantial, for example, ten feet, to accu- 23 .rately determine the condition of theroadway as to alignment of its surface, and while I have heretofore employed similar machines having a rigid frame member, I find it is difficult to house the machines when. not in use; my presentinvention provides for folding the machine to obviate, that disadvantage. '5

-VVith my present invention, oneof the frame members carries at its midxportion,

53 adjustable stops between which 'the end of a barmay move which is supported by the otherframemembenarid in this wayvariations in evenness of the roadway are indicated'by movement of the end of the "bar between the adj ustablestops. i With the proportions referred to, where the frame members are of the same length between the axes of theirsupporting wheels, the movement of the bar between the adjustable stops issub-,

stantiallyv equal tothe displacement of'the 'mid wheel from alignment with the end wheels. By my construction, I further provide a support for the indicating bar sojthat it may collapse when the machine is folded.

My invention will bestabe understood by her 11.

reference to the accompanying drawings showing a preferred embodiment thereof, in which i Fig. 1 illustrates my machine in its condition when in use, inside elevation,

Fig. 2 shows the machine illustrated in Fi 1, in side View in its folded condition,

Fig. 3 is a sectional view to an enlarged scale, of the parts shown in Fig. 1 taken along the line 3'-3,

Fig. 4 is a sectional view to an enlarged scale, of the parts shown in Fig. 1 taken along the line H, and a Fig; 5 is a detailed plan view of the hinged construction and wheel mounting of the machine.

Similar numerals refer to similar parts throughout the several. views.

As shown in Fig. 1, my machine consists of two frame members and 11 provided at their ends with forked brackets 12, 13 and 14, 15 respectively. The ends of the bracket l l'overlapthe ends of the bracket 13 and are connected by a pivot rod 16 forming the axle V of a wheell? and constituting a hinged construction supporting the mid-portlon of the machine,as shown in Flg. 5. The brackets 12 and 15 similarly support the end Wheels l8 and 19. The ends of the brackets are The frame member 11 carries mid-way between the wheels 17 and 19, two adjustable I stops 20 and .21, for example screws, threaded through supporting arms 22 and 23 carried by a bracket 24: secured to the frame mem The frame member 10 carries by suitable brackets 25 and 26, a metal tube 27, preferably substantially parallel with the frame member 1.0,said tube being about half as long as the frame member.

The tube 27 contains a bar 28which is preferably a'slidmg fit in the tube, said bar being of a length to extend adjacent thestop screws 20 and 21 and at the same time to project sufliciently into the tube 27, to give the bar positive support. The end of the bar 28 adjacent the stop screws 20 and 21, preferably carries a plate a so and 21 so that movement of the bar vertically, relatively to the frame member 11, is .limitedby the stop screws. A bracket 30 comprising a bent metal bar, is -car'ried by the frame member 11 adjacent the stop screws and 21,-around theebar 28 to protect it from being bentwhile in use, and yet permit ting free movement of the bar vertically.

{The bar 28 is preferably of metal and may a 10,

be eithersolid .or tubular as desired.

While the constructionthus far described affords a visible indication of surface irreg "ularities by movement of the plate 29 yerf tically between the stop screws 20 and 21 when the machine is rolled over a roadway being tested, Lfind 1t convenient to employ in add tiom'an aud ble lndlcation of move V merit of the plate 29=to the limitsof the tolerancepermitted in either direction, and this result is securedhymount ng on the frame member 11 means of a bra cket- 31, an electrio-battery 32 andan electric buzzer 33,

electrically connected with the arms 22. and 23 and with the plate 29 as'indicated, the arms 22 and 23 for this purpose "being insulated frointhe' braclretfle, 3

- For the construction described, where the distances between the wheels are equal to each other,-a'nd th'e axis of the stop-screws '20 and 21 is mid-way between the wheels I I 17 and-l9, the plate 29 will move between the stop screws 20' and 21",amounts substan- I tially'equaltothe dis placementof the wheel "17 from alignment with" the'wheels 18 and *535. l

-21, at distancesabove below the plate 19, and by. setting the stop screws 20' and 29 equal'to permissiblevariations in the "level or alignment oftheroadw-ay, an indication v y Q is atbn jce ihad ofjirregularities"inthe surthan the permissible? variation *from a' -straight: line *ofjthe surface of thearoadway,' a for. with the electrical connections described,

the buzzer '33 .givies an audible indication face ofthe roadway beingwithin or greater when the vertical displacement of the wheel 617 from alignmentwith tl1eavl1eels.18 and 19 reaches sald' permissible variation in either direction: i

A bracketispreferably mounted on the axle. of the wheel 19 to form astan'dfor'the m'ach ine by swinging the bracket to vertical posit on, and from the upper end of the V bracket, a handle 85'eXtends-to conveniently.

. move the machinegalong the roadway being tested; L v I v I As showntin Fig. 3,"the*frame member 10 may.convementlyconsist of two light chanfnel'fih ars and of metal,-sec'ured together .at mtervalsjby rivetsjor equivalent fasteningidevices, and in this figure I illus tratethe construction of the bracket 25, which consists of a ni'etal' bar-bent to form a; seat vat its mid porti'on for the tube'27, and having its ends. extending upon opposite sides iof the frameimemberjm and secured thereto by bolts 36. The tube'27 is held in its seat by a cap 25 fastened tothe bracket 25 by suitable screws or bolts. The bracket 26 is of the same construction as the bracket 25.

In Fig. 4 I illustrate the construction of the bracket- 30, which is bent at its mid-portion to forma vertical guideway for the bar 28, and has itsends extending upon opposite sides of the frame member 11 to which it is secured by suitable bolts 37. The frame member 11 is preferably of. the same construction as described for the frame member .10 and as shown inFig. 4 may consist of light channel bars 11? and .11 of metal, secured together in any suitable manner, for example by rivets. l I

I In the folded relation ofthe machine shown in Fig. 2, it will be observed that the frame.

members lie adjacent each other in substantially parallel relation, and in this view I illustrate the collapsed position of the rod28 in the tube 27, so that the-plate 29 does not extend beyond the wheel 1.7; A clamping screw 38 may extend through thebracket 26 and the tube 27, to holdthe rod28 either in the positionshown in Fig; 1' or thelp-osition shown'in Fig. 2 asdesire'dr My construction above described provides an accurate and dependable indicating mechparticular vembodiment above described, it will be understood that I do not limit myself to thisexact constructioi'r as I may employ equivalents known to the art at the time of the filing of this application'without departing'from the scope of the appended claims.

'WhatIclaimis:

1. Ina-road testing machine, the combination .of'two elongated longitudinally alined frame members, a hinge construction pivotally connecting the adjacent ends of said members, awhe'el rotatably mounted in said hinge construction, an additional wheel rotatably mounted onthe end portion of each of said frame members remote from said hinge construction, a rod carried by one of said frame members and extending. beyond said, hinge construction and ad acent said other frame member, and agauge pointican,

ried by said. other frame member adjacent theend of said rod and adapted toshow'vertical movement ofsaid rod'end relatively to saidgauge point, whereby movementfof one of saidwheels vertically relatively to the others ofsaid wheels moves said rod-end relatively to saidgauge point.

2. Inaroad testingmachine, the combinationiof two elongated longitudinally alined hinge, construction, a rod carried by one of said frame members and extending beyond said hinge construction and adjacent said other frame member, and a gauge point carried by said other framemember adjacent the end of said rod and adapted to show vertical movement of said rod end relatively to said gauge point, whereby movement of one of said wheels vertically relatively to the others of said wheels moves said rod end relatively to said gauge point, the distances from the axis of said mid-wheel to the axis of the other wheels being substantially equal to each other, said gauge-point being equidistant from the axes of the wheels carrying its supporting frame member, and said wheel's'being of substantially the same diameter, whereby movement of the mid-wheel relatively to the plane of the tread surfaces of said additional wheels produces a' substantially equal relative movement between said rod and said gauge point.

3. In a road testing machine, the combination of two elongated longitudinally alined frame members, a hinge construction pivotally connecting the adjacent ends of said members, a wheel rotatably mounted in said hinge construction, an additional wheel rotatably mounted on the end portion of each of said frame members remote from said hinge construction, a rod carriedby one of said frame members and extending beyond said hinge construction and adjacent said other frame member, a gauge point carried by said other frame member adjacent the end of said rod and adapted to show vertical movement of said rod end relatively to said gauge point, whereby movement of one of said wheels vertically relatively to the others of said wheels moves said rod end relatively to said gauge point, and a tube carried by said one frame member and supporting said rod, whereby said rod may be moved into said tube to lie between the ends of said one frame 7 member when the machine is not in use.

4. Ina road testing machine, the combination of two elongated longitudinally alined frame members, a hinge construction pivotally connecting the adjacent ends of said member and supporting said stops one above and the other below the end of said rod.

5. In a road testing machine, the combination of two elongated longitudinally alined frame members, a hinge construction pivotally connecting the adjacent ends of said members, a wheel rotatably mounted insaid hinge construction, anadditional wheel rosaid frame members remote from said hinge construction, a rod carried by one of said frame members and extending beyond said hinge constructionand adjacent said other frame members, a pair of gauge stops, and a bracket carried by said other frame member and supporting said stops one above and the other below the end of said rod, said stops comprising screws adjustable in said bracket towards and from said rod permitting desired amounts of movement of said rod end.

V 6. In a road testing machine, the combination of an elongated frame having a hinge dividing the frameinto two connected parts fol dable adjacent each -other when the machine is not in use, wheels carried by and supporting the frame at'its end portions and at .an'intermediate point when in its open position, and devices having relative movement and carried respectively by the two parts of the frame and indicating changes in the elevation of one of said wheels relatively to the others of saidwheels. l.

7. In a road testing machine, the combination of an elongated frame having a hinge dividing the frame into two-connected parts foldable adjacent each other when themachine is not inuse, wheels carriedby and supporting the frameat its end portions and at an intermediate point when in its open position, and devices having relative moveparts beyond said hinge and adjacent the other of said parts, and a gaugingdevice carried by said other part adjacent said memher. 7 I V I 8. In a road testing machine, the combina tion of an elongated frame having a hinge, dividing theframeinto two connected parts foldable adjacent each other when the ma-- chine is not in use, wheels carried by and supporting the frame at its end portions and at anintermediate point when inits open position,and devices having relative movement and carried respectively by the two parts of the. frame andindicating changes, in the elevation of one of said wheels rela-o tively to the others of said wheels, said parts and devices being so proportioned that the relativemovement ofsaid devices in any case substantially'equalto the change in elevatatably mounted on the end portion of each of i of said supportingframe part when the. frame of one; of said "wheels relatively to the,

iothers thereof.

9. In a} road testing machine, the combination of anelongated framehavlng a hinge dividing therframe lnto two connected parts ilfoldable adjacent each other, when the mailchine is notin 'use,-wheels carried by and supporting the frame at its end portions and a an intermediate i point when-in its open positlon, and devices having relative move- 'ment and carried-frespectively by the two parts of the frameand indicating changes in' the elevation of'oneof said wheels'rel'atively to the others ofsaidwheels, said devices com- 3 prising a member. extending from, oneof said parts beyond said hinge and adjacent the other of said parts,;and a gauglng device carried by said otherpart adjacent said member,

' in elevation of one of said wheels relatively said parts and devices being soproportioned that the relative movement of said devices in anycase is substantially equalto the change to the othersthereof; o

' 10.. In a road test ngmaohine, the combination of an elongated frame having a hinge dividing the frameYintotwo connected parts foldable adjacentfeach other when the machineis not inguse, wheels carried by and fs upporting theframe at its end portions and at an intermediate point? when in its open position, a guideway rcarriedby one of said 7 as said frame parts, a rod. movable. in said guideway' to extend beyo'ndisaid hinge and adjacent the other:of saidframe parts, and gauging devices carried said other frame (part for indicating relative movement beand movable towards and away from-said rod as desired. V

'- 12. In a road testing machine, the combination of an'elongated frame having a hinge dividing the frame into tWo .connectedparts foldable adjacent each other when the machine is not in use, wheels carried by and supporting the frame at three points when in its open position, and devices having relative movement and carried respectively by the two partsofthe frame and indicating changes in the elevation of one of said wheels relau tivel-y to theothers of said wheels, one of said wheels. having its axis coincident with said hinge axis, and the others of said wheels being equidistant from said hinge axis;

'Inwitness whereof, I hereunto subscribe my name this 13th day of December, A. D. 1928. V i

: GEORGE N; LAMB.

frame parts and directed towards the other,

tween said rod andsaid gauging devices, said rod belngat least asshort as the frame part supportingrit andioonta'ined within the length 7 parts are in folded condition. 11. In a road testing machine, the combina tion of an elongated frame having a hinge dividing the frame into, two connected parts foldableadjacenteach other when the maa chine! is'not in .u se, wheels carried by and supporting lthe frame: at its end portions and anjintermediate point, when in its open 50" position, guideway carried by one of said Jframe parts and directed towardsthe other of'said frame p'arts,a rod movable in said guideway to "extendibeyond said hinge and ofsaid supportingframe part when the frame 1 parts are in f'olded condit on, said gauging "devices comprising a bracket carried by said i otherframe part, and screws carried by said 5 bracket above and below said rod respectively 

